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$$f(t)=A_{0}+\sum_{n=1}^{\infty}A_{n}\sin(n\omega t +\varphi_{n})=\frac{a_{0}}{2}+\sum_{n=1}^{\infty}(a_{n}\cos nx+b_{n}\sin nx)$$
$$\omega = (g^{a}b^{n})y_{0}^{n}=g^{ax_{0} \bmod n}(g^{ax_{0}\, div\, n}b^{x_{0}}y_{0})^{n} \bmod n^{2}$$
$$h(m)\overset{?}{=}g^{s_{1}}s_{2}^{n} \bmod n^{2}$$
$$CR[n]\equiv D-Class[n]\Leftarrow Class[n] \Leftarrow RSA[n,n] \Leftarrow Fact[n]$$
$$\omega^{\lambda} = (1+n)^{a^{n\lambda}b^{n\lambda}} = (1+n)^{a\lambda} =1+a\lambda \bmod n^{2}$$
$$\left\{
\begin{aligned}
s_{1}& = \frac{L(h(m)^{\lambda}) \bmod n^{2}}{L(g^{\lambda} \bmod n^{2})} \bmod n \\
s_{2}& = (h(m)g^{-s_{1}})^{1/n \bmod \lambda} \bmod n
\end{aligned}
\right.$$
$$\int_{L}P(x,y)dx+Q(x,y)dy=\int^{\beta}_{\alpha}P[\varphi(t),\varphi(t)] \varphi^{'}(t) + Q[\varphi(t),\psi(t)]\psi^{'}(t)dt $$
$$S_{n} = \{{u<n^2|u = 1 \bmod n}\}$$
$$\sum_{{i<3}\atop{j<3}}i/j$$
$$(uv)^{(n)}=\sum_{k=0}^{n}C_{n}^{k}u^{(n-k)}v^{(k)}$$
\end{document} 